Enlightening the Universe behind the Milky Way bulge: I. Target selection of VVV bulge galaxies

The location of the Solar System constrains the detection of extragalactic sources beyond the Milky Way(MW) plane. The optical observations are hampered in the so--called Zone of Avoidance (ZOA) where stellar crowding and Galactic absorption are severe. Observations at longer wavelengths are needed...

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Detalles Bibliográficos
Autores: Duplancic Videla, Maria Fernanda, Alonso, Sol, Coldwell Lloveras, Georgina Vanesa, Galdeano, Daniela, Minniti, Dante, Fernandez, Maria Julia, Mesa, Valeria, Perez, Noelia Rocío, Pereyra, Luis Alberto, Pavesich, Franco
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/225018
Acceso en línea:http://hdl.handle.net/11336/225018
Access Level:acceso abierto
Palabra clave:GALAXIES: PHOTOMETRY
GALAXIES: STATISTICS
INFRARED: GALAXIES
GALAXY: BULGE
https://purl.org/becyt/ford/1.7
https://purl.org/becyt/ford/1
Descripción
Sumario:The location of the Solar System constrains the detection of extragalactic sources beyond the Milky Way(MW) plane. The optical observations are hampered in the so--called Zone of Avoidance (ZOA) where stellar crowding and Galactic absorption are severe. Observations at longer wavelengths are needed to discover new background galaxies and complete the census in the ZOA. Aims. The goal of this work is to identify galaxies behind the MW Bulge using near-infrared (NIR) data from the VISTA Variables in Vía Láctea (VVV) survey. Methods. To this end we made use of different VISTA Science Archive (VSA) tools in order to extract relevant information from more than 32 billion catalogued sources in the VVV Bulge region. We find that initial photometric restriction on sources from VSA exttt{vvvSource} table combined with restrictions on star--galaxy separation parameters obtained from Source Extractor is a successful strategy to achieve acceptable levels of contamination (60%) and a high completeness (75%) in the construction of a galaxy target sample. To decontaminate the initial target sample from Galactic sources our methodology also incorporates the visual inspection of false colour RGB images, a crucial quality control which was carried out following a specifically defined procedure. Results. Under this methodology we find 14480 galaxy candidates in the VVV Bulge region making this sample the largest catalogue to date in the ZOA. Moreover these new sources provide a extbf{fresh} picture of the Universe hidden behind the curtain of stars, dust and gas in the unexplored MW Bulge region. Conclusions. The results from this work further demonstrate the potential of the VVV/VVVX survey to find and study a large number of galaxies and extragalactic structures obscured by the MW, enlightening our knowledge of the Universe in this challenging and impressive region of the sky.